An impregnated food obtained by bringing a porous solid edible material, such as a baked confectionery, a dried food, a freeze-dried food of meat, vegetable, fruit, etc. into contact with a liquid food before or after a pressure reduction treatment or under a condition of a reduced pressure so as to impregnate the food with the liquid food, and process for producing the same have been proposed (Patent Literatures 1 to 3). By these processes, however, in a case where, for example, a thick solid edible material is impregnated with a liquid food which solidifies at room temperature, voids of the edible material are filled with the solidified liquid food, and the texture thereof becomes very hard, which is unfavorable in some occasions. To cope with this, if the impregnation is carried out at a less reduced pressure, the liquid food penetrates only to shallow zones in the solid edible material without reaching a central part thereof, thereby resulting in that a sense of unity between the solid edible material and the liquid food is impaired.
Furthermore, an impregnated food in which a porous solid edible material is impregnated with a liquid food by a first pressure reduction treatment, and then another pressure reduction treatment is carried out without immersing the solid edible material in the liquid food, so that the liquid food can be impregnated deep into the solid edible material while the liquid food inside the solid edible material let out moderately and a process for producing the same have been disclosed (Patent Literature 4).
By this method, however, in a case where, for example, the viscosity of a liquid food is high, the liquid food may occasionally not be impregnated sufficiently into a solid edible material. Further, even if the liquid food has been able to be impregnated into the solid edible material by the first pressure reduction treatment, a sufficient amount of the liquid food may not be let out by the second pressure reduction treatment, and consequently, in a case where, for example, a thick solid edible material is impregnated with a liquid food which solidifies at room temperature, the texture thereof may become too hard. To cope with the above, if various recipe modifications are made to decrease the viscosity of a liquid food, an aimed amount of the liquid food may let out, but the taste of the liquid food may become dull, which is not favorable. Additionally, it also has a disadvantage that the steps become complicated because it is necessary to carry out the pressure reduction treatment twice.